UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.110 Safari/537.36

Steps to reproduce the problem:
1. Try to build chromium with latest clang/llvm 8 from svn.
2. Build fails
3. Downgrade to llvm 7
4. Build succeeds

What is the expected behavior?

What went wrong?
[10167/19477] ACTION //third_party/perfetto/...en(//build/toolchain/linux/unbundle:default)
FAILED: gen/third_party/perfetto/protos/perfetto/config/chrome/chrome_config.pbzero.h gen/third_party/perfetto/protos/perfetto/config/chrome/chrome_config.pbzero.cc gen/third_party/perfetto/protos/perfetto/config/data_source_config.pbzero.h gen/third_party/perfetto/protos/perfetto/config/data_source_config.pbzero.cc gen/third_party/perfetto/protos/perfetto/config/data_source_descriptor.pbzero.h gen/third_party/perfetto/protos/perfetto/config/data_source_descriptor.pbzero.cc gen/third_party/perfetto/protos/perfetto/config/ftrace/ftrace_config.pbzero.h gen/third_party/perfetto/protos/perfetto/config/ftrace/ftrace_config.pbzero.cc gen/third_party/perfetto/protos/perfetto/config/inode_file/inode_file_config.pbzero.h gen/third_party/perfetto/protos/perfetto/config/inode_file/inode_file_config.pbzero.cc gen/third_party/perfetto/protos/perfetto/config/process_stats/process_stats_config.pbzero.h gen/third_party/perfetto/protos/perfetto/config/process_stats/process_stats_config.pbzero.cc gen/third_party/perfetto/protos/perfetto/config/test_config.pbzero.h gen/third_party/perfetto/protos/perfetto/config/test_config.pbzero.cc gen/third_party/perfetto/protos/perfetto/config/trace_config.pbzero.h gen/third_party/perfetto/protos/perfetto/config/trace_config.pbzero.cc 
/usr/bin/python2 ../../tools/protoc_wrapper/protoc_wrapper.py perfetto/config/chrome/chrome_config.proto perfetto/config/data_source_config.proto perfetto/config/data_source_descriptor.proto perfetto/config/ftrace/ftrace_config.proto perfetto/config/inode_file/inode_file_config.proto perfetto/config/process_stats/process_stats_config.proto perfetto/config/test_config.proto perfetto/config/trace_config.proto --protoc ./protoc --proto-in-dir ../../third_party/perfetto/protos --plugin protoc_plugin --plugin-out-dir gen/third_party/perfetto/protos --plugin-options wrapper_namespace=pbzero
--plugin_out: protoc-gen-plugin: Plugin killed by signal 4.
Protoc has returned non-zero status: 1
[10180/19477] CXX obj/third_party/metrics_proto/metrics_proto/system_profile.pb.o
ninja: build stopped: subcommand failed.

Did this work before? Yes 

Chrome version: 70.0.3538.110  Channel: stable
OS Version: Manjaro 4.19.4
Flash Version: 

Used to compile chromium fine with latest llvm until maybe 2 stable versions ago.